Detonating mechanism for a bomb fuse

ABSTRACT

A bomb fuse whose arming is dependent, inter alia, on the disposing of the fuse detonator in such a position that it is capable of detonating the booster explosive of the fuse.

United States Patent [72] Inventor ,Iakhin Boaz Popper [50] Field ofSearch 102/86, Kiryat Motzkin, Israel 85 .6, 82, 83

1211 Appl. N6. 802,111

[22] Filed Feb. 25, 1969 References Cited 1451 Patented 061. 12, 1971UNITED STATES PATENTS I 1 Assign/=9 The ism, Ministry of Defence2,544,358 3/1951 Schermuly 102/86 Tel 3,146,? 14 9/1964 Moore.....l02/85.6

i351 Priority f 1968 3,261,293 7/1966 Webb 102 82 22: PrimaryExaminer-Benjamin A. Borchelt 2 Claims, 4 Drawing Figs.

US. Cl

DETONATING MECHANISM FOR A BOMB FUSE Assistant Examiner-J. J. DevinAttorneyKirschstein, Kirschstein 8L Ottinger ABSTRACT: A bomb fuse whosearming is dependent, inter alia, on the disposing of the fuse detonatorin such a position that it is capable of detonating the boosterexplosive of the fuse.

PATENTED nm 1 219m SHEET 2 BF 2 lnvenlor TAKHlN BOA?- POPPER y ww Ma- Wff 4 A ttorneys DE'ION A'llNG MECHANISM FOR A BOMB FUSE This inventionrelates to bomb fuses and is particularly concerned with the detonatorsystem for bomb fuses of the kind whose arming is dependent, inter alia,on the disposing of the fuse detonator in such a position that it iscapable of detonating-the booster explosive of the fuse. Such a bombfuse will hereinafter be referred to as a bomb fuse of the kindspecified."

With bomb fuses of this kind various forms of mechanisms cambe employedfor moving the detonator into position for detonating the boosterexplosive. One such known mechanism is arranged to be driven by animpeller carried by the fuse and arranged to be released for rotationunder the influence of the airstream after release or launching of thebomb. Rotation of the impeller is transmitted via suitable gearing so asto displace -the detonator into an armed position vis-a-vis the boosterexplosive. with hitherto known detonator mechanisms the detonator isshielded from the booster explosive prior to the full arming of the fuseby means of a heavy brass-lead cup plate.

it is an object of the present invention to provide a new and improveddetonating mechanism for a bomb fuse.

According to the present invention there is provided a detonatingmechanism for a bomb fuse of the kind specified comprising a detonatorhousing, a recess formed in the housing adapted to receive the detonatorand communicating via a bore formed in the housing with a cavity formedin a booster explosive, a displaceable element displaceable in said borefrom a first position in which it bars communication between said recessand said cavity and a second position in which said communication cantake place and biasing means located in said recess for biasing thedetonator towards said bore so that when said element is in said firstposition said detonator abuts said element.

Preferably a further recess is formed in said housing communicating withsaid bore and designed to accommodate the igniter, said further recessbeing shielded from said first recess and from the booster explosive bysaid element when the latter is in its first position and communicatingwith the bore and the cavity in the booster when the element is in itssecond position.

Preferably the means for displacing the element from the firstto. thesecond position is as described in our copending patent applicationcopending U.S. Pat. application Ser. No. 802,l 10.

One embodiment of a bomb fuse in accordance with the present inventionwill now be described by way of example and with reference to theaccompanying drawings in which:

FIG. 1 is a partially sectioned elevation of the bomb fuse,

FIG. 2 is an elevation of the same bomb fuse partially sectioned alongthe lines llll of the view shown in Fig. 1, while FIGS. 3 and 4 aresimilar views of the bomb fuse in a second stage of operation.

As seen in the drawings, the bomb fuse comprises a casing having aconical nose portion 1 and a substantially cylindrical body portion 2, ascrew-threaded portion 3 being formed at an intermediate position on thebody portion 2 so as to enable the fuse to be screwed into the body ofthe bomb (not shown).

A rotary screw shaft 5 is coupled to an impeller (not shown) and extendsinto the cylindrical bore 6 formed in a rod 8 which depends downwardlyfrom a piston 9 constituting part of a dashpot mechanism 10. Thismechanism 10 is described in detail in our copending patent applicationcopending U.S. Pat. application Ser. No. 802,110 to which reference canbe made for further details. The cylindrical body portion includes adetonator housing 11 having a central bore 12 in which is slidable therod 8. The lowest portion of the fuse housing accommodates a boosterexplosive 13 in which is formed a traplike cavity 14 having an upperdefining wall 140 in which is formed a cavity inlet 14b, and a sidewall140 which is inclined at an acute angle with respect to the upper wall14a, communicates with the central bore 12 of the detonator housing 1']via cavity inlet 14b.

An inclined recess 15 is formed in the detonator housing 11 this recessaccommodating an elongated substantially cylindrical detonator 16 and abiasing spring 17 which bears against one end 16a of the detonator l6and biases the detonator 16 towards the central bore 12. The rod 8 isformed with a notch 18 which, in the position of the rod 8 shown in Fig.l of the drawings, is disposed adjacent the recess 15 formed in thedetonator housing 11 so that the opposite end 16b of the detonator l6remote from the biasing spring is located in the notch 18.

Diametrically opposed to the inclined recess 15 is formed a horizontalrecess 19 in which is located an electrically actuated pyrotechnicigniter mechanism 20 which is of standard construction and needtherefore not be described in any detail. The outer, electricallyconductive casing of the igniter mechanism 20 is electrically connectedto the conductive housing 11 via a compression spring 21 retained withinthe recess 19 and serving to bias the igniter mechanism away from thecentral bore 12. An insulated, arrow-shaped contact 21a bears against anopposite end of the igniter mechanism 20 and is adapted for connectionto an electric igniting circuit (not shown). When this igniting circuitis made, the igniter mechanism 20 receives an electric igniting impulsevia the contact 21a and the housing 11 as a result of which an ignitingflame is emitted by the igniting mechanism in the direction of thecentral bore 12.

As seen in Figs. 1 and 2 of the drawings with the rod 8 and the piston 9located in its downward position the detonator I6 is completely shieldedon the one hand from the igniter 20 and is prevented from falling intothe cavity 14 formed in the booster explosive 13. Furthermore by reasonof the particular manner in which the detonator 16 abuts the rod 8 thedetonator 16 is retained in its safe unarmed position irrespective ofthe accelerating forces which are exerted on the bomb fuse duringlaunching or release or in the event of a sudden premature impact.

When however as a result of the displacement of the rod 8 and itsassociated piston 9 by a mechanism for example as described in ourcopending patent specification copending U.S. Pat. application Ser. No.802,1l0the rod 8 is moved upwardly, the detonator 16 is projected bymeans of its compression spring 17 out of its recess 15 through the bore12 and into the cavity 14 formed in the booster explosive 13 and the end16a of the elongated cylindrical detonator 16 strikes the inclined wall14c of the cavity 14 and in consequence the detonator 16 turns around inthe cavity 14 so that its elongated axial dimension faces the uppercavity wall 14a. Thus the particular shape of this cavity 14 is such asto constitute a trap so that even though the fuse may suffer aconsiderable shock upon impact the detonator cannot move back into itsoriginal recess. Furthermore, as a result of the upward movement of therod 8 communication is effected between the horizontal recess 19 inwhich is located the igniter 20 via the bore 12 and the cavity 14 sothat when the igniter 20 receives its igniting impulse the flame emittedby the igniter 20 can reach the detonator 16 so as to ignite it.

While in the embodiment described above the means for displacing the rodhave been described as those illustrated and referred to in ourcopending patent application, it will be realized that any othersuitable displacing means can be employed which results in the axialdisplacement of the abutting rod after a predetermined delay period.

1 claim:

1. A detonating mechanism for a bomb fuse whose arming is dependent,inter alia, on the disposing of a fuse detonator in a position where itcan detonate a booster explosive of the fuse, said mechanism comprising:a detonator housing, a housing wall defining a first recess in which anelongated detonator is located, said housing walls further defining asecond recess, detonator-igniting means located in said second recess,said housing walls further defining a third recess in which said boosterexplosive is located, means for forming a traplike cavity in saidbooster explosive and including cavity walls defining element isdisplaced into the second position the detonator is projected by saidbiasing means through said cavity inlet into said cavity interior anddisplacement of the detonator out of the cavity is inhibited.

2. A detonating mechanism according to claim 1, wherein said rod hasformed therein a notch in which in the first position of the rod islocated the end of the detonator.

1. A detonating mechanism for a bomb fuse whose arming is dependent,inter alia, on the disposing of a fuse detonator in a position where itcan detonate a booster explosive of the fuse, said mechanism comprising:a detonator housing, a housing wall defining a first recess in which anelongated detonator is located, said housing walls further defining asecond recess, detonator-igniting means located in said second recess,said housing walls further defining a third recess in which said boosterexplosive is located, means for forming a traplike cavity in saidbooster explosive and including cavity walls defining a relativelyrestricted cavity inlet and a relatively widened cavity interior, meansforming a housing bore communicating on the one hand with said cavityinlet and on the other hand with said first and second recesses, adisplaceable element displaceable in said bore from a first position inwhich it bars communication between first and second recesses on the onehand and said cavity inlet and a second position in which saidcommunication can take place, and biasing means for biasing thedetonator toward said bore so that when the displaceable element isdisplaced into the second position the detonator is projected by saidbiasing means through said cavity inlet into said cavity interior anddisplacement of the detonator out of the cavity is inhibited.
 2. Adetonating mechanism according to claim 1, wherein said rod has formedtherein a notch in which in the first position of the rod is located theend of the detonator.